Cellulases or cellulytic enzymes are enzymes involved in hydrolysis of cellulose. In the hydrolysis of native cellulose, it is known that there are three major types of cellulase enzymes involved, namely cellobiohydrolase (1,4-.beta.-D-glucan cellobiohydrolase, EC 3.2.1.91), endo-.beta.-1,4-glucanase (endo-1,4-.beta.-D-glucan 4-glucanohydrolase, EC 3.2.1.4) and .beta.-glucosidase (EC 3.2.1.21).
Cellulases are synthesized by a large number of microorganisms which include fungi, actinomycetes, myxobacteria and true bacteria but also by plants. Especially endoglucanases of a wide variety of specificities have been identified.
A very important industrial use of cellulytic enzymes is the use for treatment of cellulosic textile or fabric, e.g. as ingredients in detergent compositions or fabric softener compositions, for bio-polishing of new fabric (garment finishing), and for obtaining a "stone-washed" look of cellulose-containing fabric, especially denim, and several methods for such treatment have been suggested, e.g. in GB-A-1 368 599, EP-A-0 307 564 and EP-A-0 435 876, WO 91/17243, WO 91/10732, WO 91/17244, PCT/DK95/000108 and PCT/DK95/00132.
Another important industrial use of cellulytic enzymes is the use for treatment of paper pulp, e.g. for improving the drainage or for deinking of recycled paper.
Especially the endoglucanases (EC No. 3.2.1.4) constitute a interesting group of hydrolases for the mentioned industrial uses. Endoglucanases catalyzes endo hydrolysis of 1,4-.beta.-D-glycosidic linkages in cellulose, cellulose derivatives (such as carboxy methyl cellulose and hydroxy ethyl cellulose), lichenin, .beta.-1,4 bonds in mixed .beta.-1,3 glucans such as cereal (.beta.-D-glucans or xyloglucans and other plant material containing cellulosic parts. The authorized name is endo-1,4-.beta.-D-glucan 4-glucano hydrolase, but the abbreviated term endoglucanase is used in the present specification. Reference can be made to T. -M. Enveri, "Microbial Cellulases" in W. M. Fogarty, Microbial Enzymes and Biotechnology, Applied Science Publishers, pp. 183-224 (1983); Methods in Enzymology, (1988) Vol.160, p.200-391 (edited by Wood, W. A. and Kellogg, S. T.); Beguin, P., "Molecular Biology of Cellulose Degradation", Annu. Rev. Microbiol. (1990), Vol. 44, pp. 219-248; Beguin, P. and Aubert, J -P., "The biological degradation of cellulose", FEMS Microbiology Reviews 13 (1994) p.25-58; Henrissat, B., "Cellulases and their interaction with cellulose", Cellulose (1994), Vol. 1, pp. 169-196.
Fungal endoglucanases have been described in numerous publications, especially those derived from species as e.g. Fusarium oxysporum, Trichoderma reesei, Trichoderma longibrachiatum, Aspergillus aculeatus, Neocallimastix patriciarum, and e.g. from species of the genera Piromyces, Humicola, Myceliophthora, Geotricum, Penicillium, Irpex.
Cellulases derived from Coprinus cinereus have been disclosed e.g. in Mardi Research Journal, 21 (2), 1993, p-179-186; Mycological Research (1991), 95, Pt.9. p.1077-81; European Journal of Biochemistry (1988), 174 (4), p. 724-732. Further, according to the latest developments in taxonomy, both Coprinus macrorhizus and Coprinus fimetarius are to be considered synonyms to Coprinus cinereus.
There is an ever existing need for providing novel cellulase enzyme preparations which may be used for applications where cellulase, preferably an endoglucanase, activity is desirable.
The object of the present invention is to provide novel enzyme preparations having substantial cellulytic activity, preferably at alkaline conditions, and improved performance in paper pulp processing, textile treatment, laundry processes and/or in animal feed; preferably novel cellulases, more preferably endoglucanases, which are contemplated to be be producible or produced by recombinant techniques.